0

A few days ago i reinstalled Xenial because I encountered the login loop problem( either from lightdm or an nvidia driver problem) similar to the one encountered in this post. Could not fix it so i reinstalled.

Now on running certain applications my screen goes pixelated;It gets completely scrambled and it takes on the colour of whatever was running and displays diagonal rows of pixels. The screen does not return and I am forced to reboot. I included the background info of the state of my computer before the reinstall so as to give an idea of the whole situation, in case that was what was causing the problem.

I also ran kali linux on the same computer and ran into the same issue once ,but only after I had reinstalled Ubuntu. Prior to that , it never had any problems.

This problem never ocurred before i reinstalled ubuntu so did that change something? Could it be a nvidia/graphics issue again, or is it just my monitor with the problem? i have included an image here:enter image description here

Just to make it explicitly clear, my problem is the screen shown in the pic above , not the login loop issue.

I also went and checked system details, and saw that graphics was shown as Gallium 0.4 on NV4C, whereas previously it was listed as Nvidia graphics drivers or something of the sort. As far as I knew i was still running NVidia drivers.

Does this change have anything to do with the problem? as requested by Elder Geek in comments, here is the output of sudo lshw -c display :

 *-display               
       description: VGA compatible controller
       product: C61 [GeForce 7025 / nForce 630a]
       vendor: NVIDIA Corporation
       physical id: d
       bus info: pci@0000:00:0d.0
       version: a2
       width: 64 bits
       clock: 66MHz
       capabilities: pm msi vga_controller bus_master cap_list rom
       configuration: driver=nouveau latency=0
       resources: irq:22 memory:ee000000-eeffffff memory:d0000000-dfffffff memory:ed000000-edffffff memory:effc0000-effdffff

one type of file that causes this is .odt.

Community
  • 1
CENTAUR
  • 3,249
  • 5
  • 22
  • 30
  • It's not clear (at least to me) what you are asking. Perhaps a link to a screenshot uploaded to imgur.com would help us help you! Thank you! – Elder Geek Dec 28 '16 at 18:01
  • i cannot take screenshots since the whole screen is scrambled and there is no response to any keyboard shortcuts. nothing can be seen except for rows of pixels, and i have to switch off the CPU. – CENTAUR Dec 28 '16 at 18:19
  • 3
    Can you take an image with your cel phone or some other device perhaps? – Elder Geek Dec 28 '16 at 18:21
  • i' ve edited the question to make it more clear. My problem is the screen as I've shown above. The stuff before was just background info that i thought may be useful to diagnose the situation. after reinstalling the login loop problem was solved. – CENTAUR Dec 29 '16 at 14:19
  • 2
    The picture looks to me like a sync problem. although that doesn't parse with the "certain applications" which might indicate a driver issue. Please [edit] your post to include the output of sudo lshw -C display You may have to open a terminal with CTRL-ALT-F1 or at least avoid running the applications that create the anomaly. – Elder Geek Dec 29 '16 at 14:28
  • i included the output of sudo lshw -C display, does it help? – CENTAUR Dec 31 '16 at 14:24
  • According to the output provided you have driver=nouveau Which "certain applications" are you having this issue with? Is it repeatable in that the same applications always cause the problem or could it be inconsistent? My bet is it's the latter and the issue is either your monitor or a damaged analog cable. – Elder Geek Jan 01 '17 at 18:20

1 Answers1

0

Its been a long time since I logged in, and I decided to post how I fixed it just in case anyone else has the same issue. The issue was that Nvidia drivers could not be recognized. You will need to go to software and updates, in the additional drivers tab. Enable the required option for 3rd party Nvidia proprietary drivers.

From what a friend of mine told me, the issue is caused by the screen attempting a graphics overlay, such as the transparent overlay generated on clicking the Ubuntu dash home button. Im not sure how or why, but that always caused a problem. Opening Libre Office tools also resulted in the same issue.

CENTAUR
  • 3,249
  • 5
  • 22
  • 30